Refrigerant deoiler



Feb. l5, 1949.

Filed NOV. l5, 1943 E. F. VILTER REFRIGERANT DE-OILER 2 Sheets-Sheet 1 Feb. 15, 1949. E. F. vlLTER REFRIGERANT DE-OILER 2 Sheets-Sheet 2 Filed NOV. 15, 1943 BY 1 l 1 ATTORNEY/6.

@a Feb. 15; 1949 BEFBIGEBANT ,DEOI'LEB Ernest F. Vilter, Milwaukee, Wis., amignor to The Viltel' Manufacturing Company, Milwaukee,

l Wis., a corporation of Wisconsin Application November 15, 1943, Serial No. 510,880 2 Claims. (Cl. (i2-115) g f My invention relates in general to improvements in devices for separating one fluid from another.

and relates more speciilcally to improvements in the constructionand operation of apparatus for deoiling liquid refrigerant or the like.

v The primary object of this invention is to provide an improved de-oiler for refrigeration systems or the like, which is simple in construction and eillcient in operation.

During prolonged operation of mechanical refrigeration systems the 'reirigerating medium frequently becomes polluted with excessive quantities of lubricating oil, and the presence of this oil l materially decreases the efilciency of the evaporators and ofthe system ingeneral. In ,order thatthe continuity' of operation of the refrigerating systems be maintained, any device for. eifecting removal of the excess oil from the refrigerant, must be adapted to function without seriously interrupting the operation -of the system, andV while prior attempts at de-oiling such cooling systems have heretofore been made, the prior oil removers were either too complicated and unreliable in action, or they undesirably disturbed the continuityl of operation'of the systems to which they were applied, or they were` relatively inefficient and too diilicult to manipulate.

It is therefore a-more specific object of the present invention to provide a new and useful refrigerant de-oliing assemblage which besides being extremely simple in construction and highly effective in use, is also reliable in operation and adapted to fimction without interfering with the normal continuous operation ofthe refrigeration system with which it cooperates.

Another speciiic object of my present invention is to provide an improved device for eifectively separating and removing liquid such as oil from circulated through a system, is utilized to actually effect the oil separation.

These and other specific objects and advantages of the present invention will be apparent from the following detailed description.

A clear conceptionv of a preferred embodiment of my, invention, and oi' the mode of constructing and of operating a refrigerant de-oiler built in accordance'with the improvement, may be hadv by referring to the drawings accompanying and forming a part of this speciilcation wherein like reference characters designate the same or similar parts of the various views.

Fig.' l is a central vertical section through a complementary pair or set of interchangeably operable refrigerant de-oiling devices, the section having been taken in the common axial plane of bothdevi'ces:- l lF18. 2 isa similarvertical section through one of the de-oilers. the section having been taken at right angles to that of F18. 1:

liquid refrigerant or the like, and for effecting constant delivery of the puriiiedrefrigerant to a continuouslyv functioning refrigeration system.

y A further speciilc object of the invention is to provide improved apparatus for rapidly and eil'ectively de-oiling a continuously operating refrigeration system without disturbing its continuityof operation.

' Still another object of this invention is to provide -va slmpliiled de-oilingasystem .which can be i manufacturedand installed-at moderate cost, and

which is conveniently manipulable to produce efc ientresults.` f Y An additional specific object-of my invention is Fig. 3 is a transverse or horizontal section through one ofthe de-oiling units, the section having been taken along the line 3 3 of Fig. 1: and Y Fig. 4 is a diagrammatic perspective view showing the mode of installing a set of the improved deoi1ing units in a refrigeration system.

While the invention has been shown and de; A

scribed herein as being especially adapted for the purpose of removing oil from liquid refrigerant in a continuously functioning refrigerating system, it is not my desire or intent to thereby unnecessarily restrict the scope or utility of the improved features some of which may be more generally applicable. v

Referring to the drawings, the improved deoiling device shown therein, comprises in general a pair of similar oil extracting units each of which consists primarily of an outer tubular casing 6; an

' inner tubular casing 1 of smaller diameter disto provide an improved refrigerant de-oiler which is extremely dependable in operation, and wherein posed centrally within the outer casing 6 and providing an intervening annular separating space or chamber 8;*upper and lower annular end heads 9, l0 respectively, for sealing the adjacent ends of the chamber 8; and a helical cooling coil il disposed within the chamber 8 and being spaced from the adjacent surfaces of both casings 6, I and maintained concentric with the common casing axis by means of elongated parallel strips i2 secured to the outer surface of the inner casing 1. v

The outer and inner casings 8, l and the end closure heads 9, I0 and strips I2 of the separating come ofthe refrigerant which is constantly being b5 units, may be formed of sheet metal -Welded or otherwise united; and while the upper end head l of each unit may be disposed perpendicular to the common longitudinal central axis of the two casings l, 1, the lower end head Il should be abruptly inclined as shown in Fig. 2. The lowermost portion of the chamber 8 of each unit is provided with an oil drain connection I2, and each of the chambers! is also provided with a lower inlet connection I4 and with an upper outlet connection Il for admitting the oil-laden refrigerant to the chamber and for deliveringthe clarined refrigerant therefrom. Each of the cooling coils I I has an upper inlet I8 and a lower outlet I1, and the lower extremity I 8 of the outer casing 6 of each unit may be formed so that the units may rest thereon in erect position.

When these improved de-oiling units are utilized in conjunction with a continuously functioning refrigeration system, they are preferably employed in sets or alternately operable pairs, connected to each other and to the piping of `the cooling system, and they are also provided with suitable control valves as indicated in the diagram of Fig. 4. In this diagram, the oil drain connection I3 of each unit is provided with an independent drain valve I9, and the lower inlet connections I4 of both units are connected to a common three-way valve 20 which is adapted to interchangeably connect these inlet connections I4 with a warm liquid supply pipe 2| having a stop valve 22 therein. The warm liquid supply pipe 2l is connected at a point between the valve 22 and the valve 20, with another three-way control valve 23 which is adapted to interchangeably connect the supply pipe 2I with the upper coil inlets I 6 past independent expansion valves 24 which may be of the thermal type. The upper outlet connections I leading from the chambers 8 are cross-connected by a pipe 25 which is communicable with the refrigeration system cold liquid supply pipe 26 past another stop valve 21, and the lower coil outlets I1 are likewise crossconnected by a pipe 28 which communicates with the suction line 29 of the cooling system past still another stop valve 30. All of these three-way, expansion and stop valves may be of standard and well known construction, and the piping system may also be provided with standard unions and other pipe fittings wherever desirable.

During normal operation of the improved deoiling system, when used in conjunction with a continuously functioning refrigeration system, the two oil removing units are alternately or interchangeably operable, so that one unit is operating to separate the oil from the refrigerant circulating through the cooling system, while the other is simultaneously warming up for discharge of the previously separated oil, and vice versa. Referring to the diagram of Fig. 4, and assuming unit A at the left to be active while unit B at the right is having the previously separated oil drained therefrom, the three-way valves 20, 23 should then be set to cause delivery of incoming oil laden refrigerant from the system to ilow only to the left unit A and not to the right unit B. The stop valves 22, 21, 30 should be open, and the drain valve I3 of unit A should be closed. Later on, after the warming up period has terminated, the drain valve of unit B should be slightly open for removal o-f the excess oil from this unit.

With the apparatus thus set or adjusted, a relatively small proportion of the liquid refrigerant flowing through the supply pipe 2| toward the de-oiling system. will pass through the valve 22 and through the expansion valve 24 of unit A, and

4 will subsequently gasify and ilow downwardly through the cooling coil Il of this active unit and will thus cool the system chamber 8 of the unit A. 'I'he greater portion of the oil laden liquid refrigerant admitted through the supply pipe 2| will however flow through the lower valve 2l and through the lower connection I4 of unit A, and will subsequently ll the chamber 8 and flow upwardly therethrough in intimate contact with the refrigerated cooling coil Il. When the oil laden refrigerant comes in contact with the cold coil II. the oil is extracted and accumulates in film formation upon this coil, and the relatively pure and cooled liquid refrigerant thereafter flows through the outlet connection Il. cross connection 25, valve 21, and discharge pipe 28 to the refrigeration system for further use. The spent refrigerant within the cooling coil II is constantly withdrawn by suction through the lower coil outlet I 1, cross connection 2l, valve 2Q and suction line 28, and this automatic oil removal may be continued until the active cooling coil II is well covered with separated oil which will adhere to the coil I I as long as it is-maintained in cold condition.

Since the three-way valves 2l, 23 have been set to cause refrigerant t''ow only through the coil II and chamber 8 of unit A, the inactive unit B will quickly warm up thereby releasing the separated oil which had previously accumulated upon the coil Il of unit B, and causing this oil to flow by gravity toward the lower outlet I3 of this unit from whence it can be removed by slightly opening the drain valve I8 just before the unit B is again thrown into service. When the unit A has been active for some time and the oil from the unit B has been completely drained, it is a simple matter to cut out unit A and to cut in unit B. This can be done by merely manipulating the three-way valves 20, 23 so as to cause the incoming oil laden refrigerant to clrculae through the unit B and not through the unit A. and by closing both drain valves I9. Such interchange of the units A, B can obviously be eected without interrupting the continuity of the refrigerating system to which the de-oiler is applied.

Because of the improved construction of the de-oiling units A, B, the oil separation and removal is thus effected in a most eiilcient manner. The construction of the casings of these-units, with inner and outer walls forming annular chambers 8 the greater portions of which are filled by the large helical cooling coils Il which however do not touch the surfaces of the adjacent casing walls 6, 1, causes the oil bearing liquid flowing through the chamber 8 to effectively contact the cooled oil accumulation surface, thus insuring rapid andiefiicient separation of the oil. The elongated spacer strips I2 form simple but effective means for centralizing the coils II within the annular chambers 8 and for preventing direct contact between the coils and casings, and the helical formation of the coils Il compels most of the refrigerant passing upwardly through the chambers to travel along similarly helical paths of great length thus also enhancing the eil'lciency of the separating umts. 'I'he provision of outer and inner elongated drums or tubular walls 6, 1 in the formation of the casings, also provides maximum radiation area or surface for warming up purposes.

From the foregoing detailed description of the construction and operation of my refrigerant deoiler, it will be apparent that the invention provides an oil removing system which is simple and compact in construction and which is moreover highly elcient in use. The improved apparatus can be readily applied to and used effectively in conjunction with various types of refrigeration systems using liquid refrigerants, without interfering with the continuity of operation of such systems. The improved de-oiling system can also be readily manipulated to rapidly and effectively separate and remove the excess oil, and while conventional manually operable valves have been shown in the diagram, these can obviously be replaced by other types of control valves which would render the system automatic. The improved assemblage has proven highly satisfactory and successful in actual use, and has'also proven far superior to any prior known apparatus for like purposes.

It should be understood that it is not desired to limit this invention to the exact details of construction or to the precise mode of operation and use, herein shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art.

I claim:

1. A refrigerant de-oiling unit comprising, outer and inner concentric tubular casings ,forming an intervening upright annular chamber, a helical cooling coil disposed coaxially of and within said chamber and being spaced slightly from the internal surfaces of said walls, valve Number means for admitting refrigerant to the upper end of said coil and to the lower portion of said chamber, and valve means for effecting drainage of oil from the lower extremity of said chamber. 2. A refrigerant de-oiling unit comprising, outer and inner concentric cylindrical casings interconnected and sealed at their adjacent ends to form an intervening annular chamber extending throughout the full length of both casings, a helical cooling coil disposed coaxial of and within said chamber and being spaced slightly from the surfaces of said casings which are exposed to said chamber, valve means for simultaneously admitting refrigerant to the opposite ends of said coil and chamber, and valve means for effecting drainage of accumulated oil from the refrigerant admission end of said chamber.

ERNEST F. VILTER..

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS y Name Date 1,500,279 Shipley July 8, 1924 1,855,615 Sperr, Jr April 26, 1932 2,137,605 'Derr Nov. 22, 1938 2,270,540 Mallory Jan. 20, 1942 2,285,123 Philipps June 2, 1942 

